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free chlorine and total chlorine problems

Hi I have a problem with cloudy water. My winter cover blew in during a terrible storm last week with basically everything going into the pool (all that junk and water). I have a 14,000 gallon pool. My readings are as followed.
CYA 50
total Chlorine 8
Free chlorine 0
ph of 7.4
alkalinity 170
total dissolved solids of 850.

I have added phosfree because my phosphates were at 1000. Now they are down to 200.
What can I do to get my free chlorine off ZERO!!! HELP! I have already shocked to pool with 4 bags of shock and 2 liquid gallons of shock.
Thanks,
Mark

Re: free chlorine and total chlorine problems

PHOSfree won't help at all. It has nothing to do with this.

High CC levels that stay about the same despite adding huge amounts of chlorine are the result of a fair bit of ammonia getting into the pool. That can come from fertilizer getting into the pool, or CYA breaking down over the winter, or someone pouring a bottle of ammonia into the water.

There are only two possible solutions. Nearly all the time the best solution is to just keep adding chlorine until the CC is finally all gone. The second option, if the ammonia level is really really high, is to replace water to get the ammonia level down. If you are worried about it you can get an ammonia measurement or do an extreme chlorine demand test to see approximately how much chlorine you are going to need to use.

Re: free chlorine and total chlorine problems

Good, it took less that 86 ppm of chlorine to clear up the water. We don't know exactly how much less, but that puts an upper bound on how much chlorine you will need to use.

I suggest you add about three large jugs of bleach (a little over 4 gallons), give it an hour to mix in, test the FC level, and as long as FC is below 10, repeat. If your test was done correctly, you will need to do that somewhere between once and five times.

Re: free chlorine and total chlorine problems

Hi jasonlion,
The pool store said it could clear up on it's own. That the combined chlorine will lower naturally and I don't need to shock. They said that with the cold water and sunshine it will go down. I am not sure to believe them. What do you think?

Re: free chlorine and total chlorine problems

Their advice really make no sense in the situation. While normal levels of chlorine plus sunlight will break down CC, you can't maintain normal FC levels. Even if you could maintain an FC level, you have enough ammonia in the water that breaking it all down that way would take months. Meanwhile, you wouldn't be able to swim because you can't maintain an FC level.

Re: free chlorine and total chlorine problems

I don't trust them. My pool is cloudy and the did tell me to use the phosphate remover. They don't seem to know what they are doing. I am planning on shocking tonight. Thanks for your advice, I really appreciate all of your help. You are the best!

Re: free chlorine and total chlorine problems

The bacterial conversion of CYA into ammonia when the chlorine levels gets to near zero is something that can happen to anyone if they don't maintain the proper chlorine level at all times. It happened to me and you can see a log of my readings and how much chlorine it took in this post. Note that it took frequent additions of chlorine multiple times during the day before I started to get an FC reading and then it took time for the water to clear and for the FC to hold (decline at normal levels -- note that I have a mostly opaque electric pool cover).

Re: free chlorine and total chlorine problems

Chlorine is chlorine, it doesn't matter to the CC level where it comes from. The main issue when selecting a source of chlorine is the other things it adds to the water. Dichlor adds a lot of CYA, which often causes problems. Cal-hypo adds calcium, which is occasionally a problem. Generally bleach/liquid chlorine is the best to use because it doesn't add anything you don't want.